I snap a line at the bottom...½" less than the shingle height, measuring from the drip edge so the shingles hangs ½" over.
Every couple of courses after that..Just how I do it.

 

Snap first line 1/2" to quarter out depending on how bad roof is. Then I'll run like 5 courses or so before another. I'll often run the pattern as far as I can before I have to restart it. Then I'll resnap. Mostly do repairs though, so I don't often end up snapping a lot of lines.

 

Only over large obstacles, or small eave width to wider ridge width.

 

I ALWAYS snap lines to allow for a full exposed course below the caps. I'll find the true peak and measure down anywhere between 3" & 3-1/2" depending upon pitch. I'll run some courses up from the bottom and then pull diagonals from the line I snapped at the ridge and mark 11's (for 5-3/4" exposure shingles).

 

12,17,22,32,42 ect... metric

 

I snap a line for the first row to keep it 1/2" down and straight. Don't snap anything after that until I get close to the top.

Has anyone ever seen a roof where you could see the rows where a guy snapped lines after it was finished?

I have seen a few. Some shingles are worse than others but what happens is they snap lines say every 8 rows but they always come down to low, so the bottom of the shingles in that row have a funky looking shadow/reveal that looks like crap. You'll know it when you see a roof that has been done that way. Most people don't look at roofs directly enough to notice but I guarantee and HO will go out after their nice new roof is installed and notice...

For me its more likely that snapping multiple chalk lines will screw things up than just snapping the first one and going with it.

 

we snap 18 1/2 from roofedge then 11 1/8", 22 1/4, 33 3/8, 44 1/2 ect.

works great. nice straight rows every time

 

Bad shingles or inexperienced installers. Sorry but a waste of good chalk.

 

I may waste chalk but every one of my roofs has an equal exposure up to the ridge cap. Irks the sh*t out of me to see 2" exposure top course below the caps.

Most people don't roof for aesthetics, so I guess I can't blame your position.

 

Straight runs with no lines is one thing a cut up roof that meets in random places is another.

 

Archi's i snap my line for my starter, then align my first normal shingle with that and i can keep things perfect going up.
3 tabs i snap the same baseline, then square off that for a vertical bond line, then i measure over half the width of a tab and snap a parallel line.
If i must past a obstruction i snap a line through (higher) and use it as a reference point for the shorter actual lines.

 

I tell you what I snap the second row of shingle instead of the first for example OC shingles I snap an 18 1/2" line. This way especially on tear offs if the eve is not straight you can run your first course with the eve and the second course will make up for any varience in the eve. Just my opinion.

 

I usually have new gutter apron to set my starters, then use my eyeballs to keep them straight...
I might pop one as I approach the ridge.

Usually only use the chalk for cutting Kansas Valleys..,

 

Whats a Kansas valley?

I snap lines every 5 shingles. I wouldn't always snap lines BUT two guys on the same section are always going to nail slightly different.

 

Whats a Kansas valley?

I guess some call it a California or cut...But I figured Cali gets too much credit:whistling

:laughing:

 

No reason to snap lines unless as mentioned, over a large dormer or another obstacle.

 

Is that a Cali special ridge cap , gota love that style.:thumbsup:

Yup!

Edit- I think that would be an Arkansas Ridge Cap

 

I snap lines in valleys, and over (some) dormers. On really old buildings with crooked fascia, I snap a line for the second course to run straight if I think it'll be an issue.

 

I snap lines when I cut plywood...and in long valleys...unless I'm laying 3tab which is never

 

I snap first line for starter course. depending on the roof system I will run shingles aproximatly halfway up the roof and snape one more line just to make sure everything is straight when we get up to the cap

 

Can't you just tell if your straight...straight shingles stay straight...if I actually think I'm crooked ill just run a tape measure up from 25 30ft depending in my tape measure

 

I guess my crew takes a little more pride in our work. We snap lines for every row 100% of the time.

 

What a waste of time.
I reckon its more inexperience then pride.

 

I can't believe how many people have trouble running shingles straight. I don't think we ever snapped lines and haven't had problems running shingles straight.

 

It takes all of 30 seconds, or less, for 2 people to snap a line.

 

Well it's not inexperience at all. We use one man as a nailer and one man as a flopper we put shingles on at a pretty fast pace and just was always in the practice of chalking lines. Sorry if I afended you. You as well probably do take pride in your work. Just one of those things we are use to doing seems to only take a few minutes and it assures me that when I go do a roof inspection on one of our jobs there will be no excuses for shingle rows to be up and down across the roof.

 

have to admit...i am only an occasional roofer...with ocd. so I snap every single line, and measure out and divide the difference to get perfect spacing to the ridge caps. sometimes i eat myself out of extra profit for the time I put into it, but i can walk away and it doesnt bother me. but like I said...only an occasional roofer. I think that if i did more of them, id definitely let things go for production and efficiency.

 

The last roof I did the shingles varied slightly in width, so the courses we snapped lines on looked less straight than the ones we tabbed...